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1.
Nat Commun ; 12(1): 4730, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354063

RESUMO

Brain organoids derived from human pluripotent stem cells provide a highly valuable in vitro model to recapitulate human brain development and neurological diseases. However, the current systems for brain organoid culture require further improvement for the reliable production of high-quality organoids. Here, we demonstrate two engineering elements to improve human brain organoid culture, (1) a human brain extracellular matrix to provide brain-specific cues and (2) a microfluidic device with periodic flow to improve the survival and reduce the variability of organoids. A three-dimensional culture modified with brain extracellular matrix significantly enhanced neurogenesis in developing brain organoids from human induced pluripotent stem cells. Cortical layer development, volumetric augmentation, and electrophysiological function of human brain organoids were further improved in a reproducible manner by dynamic culture in microfluidic chamber devices. Our engineering concept of reconstituting brain-mimetic microenvironments facilitates the development of a reliable culture platform for brain organoids, enabling effective modeling and drug development for human brain diseases.


Assuntos
Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologia , Dispositivos Lab-On-A-Chip , Neurogênese/fisiologia , Organoides/crescimento & desenvolvimento , Organoides/fisiologia , Animais , Encéfalo/citologia , Meios de Cultura , Fenômenos Eletrofisiológicos , Matriz Extracelular/fisiologia , Estudos de Viabilidade , Perfilação da Expressão Gênica , Humanos , Hidrogéis , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Modelos Anatômicos , Modelos Neurológicos , Neurogênese/genética , Neuroglia/citologia , Neuroglia/fisiologia , Técnicas de Cultura de Órgãos/instrumentação , Técnicas de Cultura de Órgãos/métodos , Organoides/citologia , Suínos
2.
Int J Mol Sci ; 22(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361042

RESUMO

Various neurodegenerative disorders are associated with human NTE/PNPLA6 dysfunction. Mechanisms of neuropathogenesis in these diseases are far from clearly elucidated. Hereditary spastic paraplegia belongs to a type of neurodegeneration associated with NTE/PNLPLA6 and is implicated in neuron death. In this study, we used Drosophila melanogaster to investigate the consequences of neuronal knockdown of swiss cheese (sws)-the evolutionarily conserved ortholog of human NTE/PNPLA6-in vivo. Adult flies with the knockdown show longevity decline, locomotor and memory deficits, severe neurodegeneration progression in the brain, reactive oxygen species level acceleration, mitochondria abnormalities and lipid droplet accumulation. Our results suggest that SWS/NTE/PNPLA6 dysfunction in neurons induces oxidative stress and lipid metabolism alterations, involving mitochondria dynamics and lipid droplet turnover in neurodegeneration pathogenesis. We propose that there is a complex mechanism in neurological diseases such as hereditary spastic paraplegia, which includes a stress reaction, engaging mitochondria, lipid droplets and endoplasmic reticulum interplay.


Assuntos
Encéfalo/metabolismo , Proteínas de Drosophila/metabolismo , Gotículas Lipídicas/metabolismo , Mitocôndrias/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Encéfalo/citologia , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Drosophila melanogaster , Metabolismo dos Lipídeos , Mitocôndrias/ultraestrutura , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Estresse Oxidativo
3.
Nature ; 596(7871): 257-261, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34349261

RESUMO

An animal's nervous system changes as its body grows from birth to adulthood and its behaviours mature1-8. The form and extent of circuit remodelling across the connectome is unknown3,9-15. Here we used serial-section electron microscopy to reconstruct the full brain of eight isogenic Caenorhabditis elegans individuals across postnatal stages to investigate how it changes with age. The overall geometry of the brain is preserved from birth to adulthood, but substantial changes in chemical synaptic connectivity emerge on this consistent scaffold. Comparing connectomes between individuals reveals substantial differences in connectivity that make each brain partly unique. Comparing connectomes across maturation reveals consistent wiring changes between different neurons. These changes alter the strength of existing connections and create new connections. Collective changes in the network alter information processing. During development, the central decision-making circuitry is maintained, whereas sensory and motor pathways substantially remodel. With age, the brain becomes progressively more feedforward and discernibly modular. Thus developmental connectomics reveals principles that underlie brain maturation.


Assuntos
Encéfalo/citologia , Encéfalo/crescimento & desenvolvimento , Caenorhabditis elegans/citologia , Conectoma , Modelos Neurológicos , Vias Neurais , Sinapses/fisiologia , Envelhecimento/metabolismo , Animais , Encéfalo/anatomia & histologia , Encéfalo/ultraestrutura , Caenorhabditis elegans/anatomia & histologia , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/ultraestrutura , Individualidade , Interneurônios/citologia , Microscopia Eletrônica , Neurônios/citologia , Comportamento Estereotipado
4.
Zoolog Sci ; 38(4): 317-325, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34342952

RESUMO

Many insects in temperate regions avoid environmental adversity for reproduction, and thus enter reproductive diapause according to photoperiod. This reproductive diapause is induced by inhibition of juvenile hormone biosynthesis in the corpus allatum. Some neuropeptides that have an effect on juvenile hormone biosynthesis have been detected in insect brains. Thus, the reproductive diapause may be photoperiodically regulated by these juvenile hormones-controlling neuropeptides. However, there is limited understanding of how the neurons expressing these neuropeptides respond to the photoperiod and control the peptide release accordingly. Here, we performed electrophysiological analyses in the pars intercerebralis (PI) of Plautia stali, where juvenile hormone inhibitory neuropeptides, Plautia stali myoinhibitory peptides (Plast-MIPs) are expressed. We found that the large neurons in the PI showed very high firing activity under diapause-inducing short day conditions. Neurotracer staining revealed that all recorded neurons projected to the nervus corporis cardiaci 1, which is known to be connected to the corpus cardiacum-corpus allatum complex. Finally, we determined how many of the large PI cells expressed Plast-MIP by single cell reverse transcription PCR. About half of large PI neurons coexpressed Plast-Mip and other neuropeptides, Diuretic hormone 44 and insulin-like peptide 1. The remaining cells only expressed Diuretic hormone 44 and insulin-like peptide 1. The present results suggested that large PI neurons, including Plast-MIP neurons, have enhanced activity under short day conditions, which may increase Plast-MIP release to the corpus cardiacum-corpus allatum complex and thus contribute to reproductive diapause.


Assuntos
Heterópteros/fisiologia , Fotoperíodo , Animais , Encéfalo/citologia , Diapausa , Feminino , Regulação da Expressão Gênica/fisiologia , Regulação da Expressão Gênica/efeitos da radiação , Neurônios/fisiologia , Neuropeptídeos/genética , Neuropeptídeos/metabolismo
5.
Neuron ; 109(17): 2649-2662, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34242564

RESUMO

Memory formation is dynamic in nature, and acquisition of new information is often influenced by previous experiences. Memories sharing certain attributes are known to interact so that retrieval of one increases the likelihood of retrieving the other, raising the possibility that related memories are organized into associative mnemonic structures of interconnected representations. Although the formation and retrieval of single memories have been studied extensively, very little is known about the brain mechanisms that organize and link related memories. Here we review studies that suggest the existence of mnemonic structures in humans and animal models. These studies suggest three main dimensions of experience that can serve to organize related memories: time, space, and perceptual/conceptual similarities. We propose potential molecular, cellular, and systems mechanisms that might support organization of memories according to these dimensions.


Assuntos
Encéfalo/fisiologia , Memória , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Humanos , Neurônios/metabolismo , Neurônios/fisiologia
6.
Int J Mol Sci ; 22(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34299328

RESUMO

The blood-brain barrier (BBB) regulates the delivery of oxygen and important nutrients to the brain through active and passive transport and prevents neurotoxins from entering the brain. It also has a clearance function and removes carbon dioxide and toxic metabolites from the central nervous system (CNS). Several drugs are unable to cross the BBB and enter the CNS, adding complexity to drug screens targeting brain disorders. A well-functioning BBB is essential for maintaining healthy brain tissue, and a malfunction of the BBB, linked to its permeability, results in toxins and immune cells entering the CNS. This impairment is associated with a variety of neurological diseases, including Alzheimer's disease and Parkinson's disease. Here, we summarize current knowledge about the BBB in neurodegenerative diseases. Furthermore, we focus on recent progress of using human-induced pluripotent stem cell (iPSC)-derived models to study the BBB. We review the potential of novel stem cell-based platforms in modeling the BBB and address advances and key challenges of using stem cell technology in modeling the human BBB. Finally, we highlight future directions in this area.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Doenças Neurodegenerativas/metabolismo , Animais , Barreira Hematoencefálica/citologia , Barreira Hematoencefálica/patologia , Encéfalo/irrigação sanguínea , Circulação Cerebrovascular , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Modelos Biológicos , Doenças Neurodegenerativas/patologia
7.
Nature ; 596(7870): 92-96, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34321664

RESUMO

The mammalian brain develops through a complex interplay of spatial cues generated by diffusible morphogens, cell-cell interactions and intrinsic genetic programs that result in probably more than a thousand distinct cell types. A complete understanding of this process requires a systematic characterization of cell states over the entire spatiotemporal range of brain development. The ability of single-cell RNA sequencing and spatial transcriptomics to reveal the molecular heterogeneity of complex tissues has therefore been particularly powerful in the nervous system. Previous studies have explored development in specific brain regions1-8, the whole adult brain9 and even entire embryos10. Here we report a comprehensive single-cell transcriptomic atlas of the embryonic mouse brain between gastrulation and birth. We identified almost eight hundred cellular states that describe a developmental program for the functional elements of the brain and its enclosing membranes, including the early neuroepithelium, region-specific secondary organizers, and both neurogenic and gliogenic progenitors. We also used in situ mRNA sequencing to map the spatial expression patterns of key developmental genes. Integrating the in situ data with our single-cell clusters revealed the precise spatial organization of neural progenitors during the patterning of the nervous system.


Assuntos
Encéfalo/citologia , Encéfalo/embriologia , Análise de Célula Única , Transcriptoma , Animais , Animais Recém-Nascidos/genética , Encéfalo/anatomia & histologia , Feminino , Gastrulação/genética , Masculino , Camundongos , Tubo Neural/anatomia & histologia , Tubo Neural/citologia , Tubo Neural/embriologia
8.
Methods Mol Biol ; 2277: 133-142, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34080149

RESUMO

Mitochondria are targets of newly synthesized drugs and being tested for the treatment of various diseases caused or accompanied by disruption of cellular bioenergetics. In drug development, it is necessary to test for drug-induced changes in mitochondrial enzyme activity that may be related to therapeutic or adverse drug effects. Measurement of drug effect on mitochondrial oxygen consumption kinetics and/or protective effects of drugs against calcium-induced inhibition of the mitochondrial respiration can be used for the study mitochondrial toxicity and neuroprotective effects of drugs. Supposing that the drug-induced inhibition of the mitochondrial respiratory rate and/or individual mitochondrial complexes is associated with adverse drug effects, the effects of drugs on mitochondrial respiration in isolated mitochondria allow selection of novel molecules that are relatively safe for mitochondrial toxicity.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Animais , Encéfalo/citologia , Avaliação Pré-Clínica de Medicamentos/instrumentação , Complexo I de Transporte de Elétrons/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Suínos
9.
Methods Mol Biol ; 2277: 357-370, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34080162

RESUMO

Subcellular fractionation is a valuable procedure in cell biology to separate and purify various subcellular constituents from one another, i.e., nucleus, cytosol, membranes/organelles, and cytoskeleton. The procedure relies on the use of differential centrifugation of cell and tissue homogenates. Fractionated subcellular organelles may be subjected to additional purification steps that enable the isolation of specific cellular sub-compartments, including interorganellar membrane contact sites. Here we outline a protocol tailored to the isolation of mitochondria, mitochondria-associated ER membranes (MAMs), and glycosphingolipid enriched microdomains (GEMs) from the adult mouse brain, primary neurospheres, and murine embryonic fibroblasts (MEFs). We also provide a detailed protocol for the purification of synaptosomes and their corresponding MAMs .


Assuntos
Encéfalo/citologia , Técnicas Citológicas/métodos , Membranas Intracelulares/química , Microdomínios da Membrana/química , Animais , Retículo Endoplasmático/química , Fibroblastos/citologia , Glicoesfingolipídeos/química , Camundongos , Mitocôndrias/química , Membranas Mitocondriais , Neurônios/química , Sinaptossomos/química
10.
Commun Biol ; 4(1): 656, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34079050

RESUMO

Pharmacological reversal of brain aging is a long-sought yet challenging strategy for the prevention and treatment of age-related neurodegeneration, due to the diverse cell types and complex cellular pathways impacted by the aging process. Here, we report the genome-wide reversal of transcriptomic aging signatures in multiple major brain cell types, including glial and mural cells, by systemic glucagon-like peptide-1 receptor (GLP-1R) agonist (GLP-1RA) treatment. The age-related expression changes reversed by GLP-1RA encompass both shared and cell type-specific functional pathways that are implicated in aging and neurodegeneration. Concomitantly, Alzheimer's disease (AD)-associated transcriptomic signature in microglia that arises from aging is reduced. These results show the feasibility of reversing brain aging by pharmacological means, provide mechanistic insights into the neurological benefits of GLP-1RAs, and imply that GLP-1R agonism may be a generally applicable pharmacological intervention for patients at risk of age-related neurodegeneration.


Assuntos
Encéfalo/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Neuroglia/efeitos dos fármacos , Envelhecimento/efeitos dos fármacos , Envelhecimento/genética , Doença de Alzheimer/genética , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Exenatida/farmacologia , Estudos de Viabilidade , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/genética , Neuroglia/metabolismo , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética
11.
Nat Methods ; 18(7): 771-774, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34168373

RESUMO

We develop an automatic method for synaptic partner identification in insect brains and use it to predict synaptic partners in a whole-brain electron microscopy dataset of the fruit fly. The predictions can be used to infer a connectivity graph with high accuracy, thus allowing fast identification of neural pathways. To facilitate circuit reconstruction using our results, we develop CIRCUITMAP, a user interface add-on for the circuit annotation tool CATMAID.


Assuntos
Encéfalo/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Sinapses/fisiologia , Animais , Encéfalo/citologia , Bases de Dados Factuais , Drosophila melanogaster , Microscopia Eletrônica , Vias Neurais
12.
Science ; 373(6553)2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34083447

RESUMO

The meninges are a membranous structure enveloping the central nervous system (CNS) that host a rich repertoire of immune cells mediating CNS immune surveillance. Here, we report that the mouse meninges contain a pool of monocytes and neutrophils supplied not from the blood but by adjacent skull and vertebral bone marrow. Under pathological conditions, including spinal cord injury and neuroinflammation, CNS-infiltrating myeloid cells can originate from brain borders and display transcriptional signatures distinct from their blood-derived counterparts. Thus, CNS borders are populated by myeloid cells from adjacent bone marrow niches, strategically placed to supply innate immune cells under homeostatic and pathological conditions. These findings call for a reinterpretation of immune-cell infiltration into the CNS during injury and autoimmunity and may inform future therapeutic approaches that harness meningeal immune cells.


Assuntos
Células da Medula Óssea/fisiologia , Doenças do Sistema Nervoso Central/imunologia , Sistema Nervoso Central/imunologia , Meninges/imunologia , Células Mieloides/fisiologia , Crânio/anatomia & histologia , Coluna Vertebral/anatomia & histologia , Animais , Medula Óssea/fisiologia , Encéfalo/citologia , Encéfalo/imunologia , Encéfalo/fisiologia , Movimento Celular , Sistema Nervoso Central/citologia , Doenças do Sistema Nervoso Central/patologia , Dura-Máter/citologia , Dura-Máter/imunologia , Dura-Máter/fisiologia , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Homeostase , Meninges/citologia , Meninges/fisiologia , Camundongos , Monócitos/fisiologia , Neutrófilos/fisiologia , Medula Espinal/citologia , Medula Espinal/imunologia , Medula Espinal/fisiologia , Traumatismos da Medula Espinal/imunologia , Traumatismos da Medula Espinal/patologia
13.
Development ; 148(12)2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34121117

RESUMO

The Ciona larva has served as a unique model for understanding the development of dopaminergic cells at single-cell resolution owing to the exceptionally small number of neurons in its brain and its fixed cell lineage during embryogenesis. A recent study suggested that the transcription factors Fer2 and Meis directly regulate the dopamine synthesis genes in Ciona, but the dopaminergic cell lineage and the gene regulatory networks that control the development of dopaminergic cells have not been fully elucidated. Here, we reveal that the dopaminergic cells in Ciona are derived from a bilateral pair of cells called a9.37 cells at the center of the neural plate. The a9.37 cells divide along the anterior-posterior axis, and all of the descendants of the posterior daughter cells differentiate into the dopaminergic cells. We show that the MAPK pathway and the transcription factor Otx are required for the expression of Fer2 in the dopaminergic cell lineage. Our findings establish the cellular and molecular framework for fully understanding the commitment to dopaminergic cells in the simple chordate brain.


Assuntos
Encéfalo/citologia , Encéfalo/metabolismo , Diferenciação Celular/genética , Ciona/genética , Neurônios Dopaminérgicos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Fatores de Transcrição Otx/genética , Animais , Biomarcadores , Linhagem da Célula/genética , Ciona/citologia , Neurônios Dopaminérgicos/citologia , Imunofluorescência , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Placa Neural/citologia , Placa Neural/metabolismo , Fatores de Transcrição Otx/metabolismo , Transdução de Sinais
14.
Nat Commun ; 12(1): 3915, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34168140

RESUMO

Memory is supported by a specific collection of neurons distributed in broad brain areas, an engram. Despite recent advances in identifying an engram, how the engram is created during memory formation remains elusive. To explore the relation between a specific pattern of input activity and memory allocation, here we target a sparse subset of neurons in the auditory cortex and thalamus. The synaptic inputs from these neurons to the lateral amygdala (LA) are not potentiated by fear conditioning. Using an optogenetic priming stimulus, we manipulate these synapses to be potentiated by the learning. In this condition, fear memory is preferentially encoded in the manipulated cell ensembles. This change, however, is abolished with optical long-term depression (LTD) delivered shortly after training. Conversely, delivering optical long-term potentiation (LTP) alone shortly after fear conditioning is sufficient to induce the preferential memory encoding. These results suggest a synaptic plasticity-dependent competition rule underlying memory formation.


Assuntos
Memória/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Complexo Nuclear Basolateral da Amígdala/fisiologia , Encéfalo/citologia , Encéfalo/fisiologia , Condicionamento Clássico/fisiologia , Potenciais Evocados Auditivos , Medo/fisiologia , Halorrodopsinas/genética , Halorrodopsinas/metabolismo , Aprendizagem/fisiologia , Potenciação de Longa Duração/fisiologia , Camundongos Endogâmicos C57BL , Neurônios/fisiologia , Optogenética
15.
Nat Commun ; 12(1): 3416, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099706

RESUMO

APOE and Trem2 are major genetic risk factors for Alzheimer's disease (AD), but how they affect microglia response to Aß remains unclear. Here we report an APOE isoform-specific phospholipid signature with correlation between human APOEε3/3 and APOEε4/4 AD brain and lipoproteins from astrocyte conditioned media of APOE3 and APOE4 mice. Using preclinical AD mouse models, we show that APOE3 lipoproteins, unlike APOE4, induce faster microglial migration towards injected Aß, facilitate Aß uptake, and ameliorate Aß effects on cognition. Bulk and single-cell RNA-seq demonstrate that, compared to APOE4, cortical infusion of APOE3 lipoproteins upregulates a higher proportion of genes linked to an activated microglia response, and this trend is augmented by TREM2 deficiency. In vitro, lack of TREM2 decreases Aß uptake by APOE4-treated microglia only, suggesting TREM2-APOE interaction. Our study elucidates phenotypic and transcriptional differences in microglial response to Aß mediated by APOE3 or APOE4 lipoproteins in preclinical models of AD.


Assuntos
Doença de Alzheimer/patologia , Apolipoproteína E3/metabolismo , Apolipoproteína E4/metabolismo , Encéfalo/patologia , Microglia/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Apolipoproteína E3/administração & dosagem , Apolipoproteína E3/genética , Apolipoproteína E4/administração & dosagem , Apolipoproteína E4/genética , Encéfalo/citologia , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Mutação , Fosfolipídeos/metabolismo , Presenilina-1/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA-Seq , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo
16.
Nat Commun ; 12(1): 3826, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34158507

RESUMO

Single-cell omics is the fastest-growing type of genomics data in the literature and public genomics repositories. Leveraging the growing repository of labeled datasets and transferring labels from existing datasets to newly generated datasets will empower the exploration of single-cell omics data. However, the current label transfer methods have limited performance, largely due to the intrinsic heterogeneity among cell populations and extrinsic differences between datasets. Here, we present a robust graph artificial intelligence model, single-cell Graph Convolutional Network (scGCN), to achieve effective knowledge transfer across disparate datasets. Through benchmarking with other label transfer methods on a total of 30 single cell omics datasets, scGCN consistently demonstrates superior accuracy on leveraging cells from different tissues, platforms, and species, as well as cells profiled at different molecular layers. scGCN is implemented as an integrated workflow as a python software, which is available at https://github.com/QSong-github/scGCN .


Assuntos
Algoritmos , Inteligência Artificial , Genômica/métodos , Redes Neurais de Computação , Análise de Célula Única/métodos , Células A549 , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Perfilação da Expressão Gênica/métodos , Humanos , Internet , Rim/citologia , Rim/metabolismo , Pulmão/citologia , Pulmão/metabolismo , Camundongos , Software
17.
ACS Appl Mater Interfaces ; 13(27): 31474-31484, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34192459

RESUMO

Owing to several key attributes, diamond is an attractive candidate material for neural interfacing electrodes. The emergence of additive-manufacturing (AM) of diamond-based materials has addressed multiple challenges associated with the fabrication of diamond electrodes using the conventional chemical vapor deposition (CVD) approach. Unlike the CVD approach, AM methods have enabled the deposition of three-dimensional diamond-based material at room temperature. This work demonstrates the feasibility of using laser metal deposition to fabricate diamond-titanium hybrid electrodes for neuronal interfacing. In addition to exhibiting a high electrochemical capacitance of 1.1 mF cm-2 and a low electrochemical impedance of 1 kΩ cm2 at 1 kHz in physiological saline, these electrodes exhibit a high degree of biocompatibility assessed in vitro using cortical neurons. Furthermore, surface characterization methods show the presence of an oxygen-rich mixed-phase diamond-titanium surface along the grain boundaries. Overall, we demonstrated that our unique approach facilitates printing biocompatible titanium-diamond site-specific coating-free conductive hybrid surfaces using AM, which paves the way to printing customized electrodes and interfacing implantable medical devices.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Encéfalo/citologia , Diamante/química , Neurônios/efeitos dos fármacos , Impressão Tridimensional , Titânio/química , Animais , Impedância Elétrica , Neurônios/citologia , Oxigênio/química , Propriedades de Superfície
18.
Nat Commun ; 12(1): 3545, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112806

RESUMO

Multiplexed fluorescence in situ hybridization techniques have enabled cell-type identification, linking transcriptional heterogeneity with spatial heterogeneity of cells. However, inaccurate cell segmentation reduces the efficacy of cell-type identification and tissue characterization. Here, we present a method called Spot-based Spatial cell-type Analysis by Multidimensional mRNA density estimation (SSAM), a robust cell segmentation-free computational framework for identifying cell-types and tissue domains in 2D and 3D. SSAM is applicable to a variety of in situ transcriptomics techniques and capable of integrating prior knowledge of cell types. We apply SSAM to three mouse brain tissue images: the somatosensory cortex imaged by osmFISH, the hypothalamic preoptic region by MERFISH, and the visual cortex by multiplexed smFISH. Here, we show that SSAM detects regions occupied by known cell types that were previously missed and discovers new cell types.


Assuntos
Encéfalo/citologia , Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Hibridização in Situ Fluorescente/métodos , Análise de Célula Única/métodos , Algoritmos , Animais , Encéfalo/diagnóstico por imagem , Simulação por Computador , Camundongos , Neurônios/citologia , Neurônios/metabolismo , Área Pré-Óptica/citologia , Área Pré-Óptica/diagnóstico por imagem , Córtex Somatossensorial/citologia , Córtex Somatossensorial/diagnóstico por imagem , Transcriptoma/genética , Córtex Visual/citologia , Córtex Visual/diagnóstico por imagem
19.
Nat Commun ; 12(1): 3292, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078910

RESUMO

Autophagy regulates primary cilia formation, but the underlying mechanism is not fully understood. In this study, we identify NIMA-related kinase 9 (NEK9) as a GABARAPs-interacting protein and find that NEK9 and its LC3-interacting region (LIR) are required for primary cilia formation. Mutation in the LIR of NEK9 in mice also impairs in vivo cilia formation in the kidneys. Mechanistically, NEK9 interacts with MYH9 (also known as myosin IIA), which has been implicated in inhibiting ciliogenesis through stabilization of the actin network. MYH9 accumulates in NEK9 LIR mutant cells and mice, and depletion of MYH9 restores ciliogenesis in NEK9 LIR mutant cells. These results suggest that NEK9 regulates ciliogenesis by acting as an autophagy adaptor for MYH9. Given that the LIR in NEK9 is conserved only in land vertebrates, the acquisition of the autophagic regulation of the NEK9-MYH9 axis in ciliogenesis may have possible adaptive implications for terrestrial life.


Assuntos
Autofagia/genética , Cílios/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Cadeias Pesadas de Miosina/genética , Quinases Relacionadas a NIMA/genética , Sequência de Aminoácidos , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Linhagem Celular , Cílios/genética , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Rim/citologia , Rim/metabolismo , Fígado/citologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Miocárdio/citologia , Miocárdio/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Quinases Relacionadas a NIMA/deficiência , Ligação Proteica , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais
20.
Cell Physiol Biochem ; 55(S3): 108-130, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34043299

RESUMO

Transient receptor potential vanilloid (TRPV) channels are part of the TRP channel superfamily and named after the first identified member TRPV1, that is sensitive to the vanillylamide capsaicin. Their overall structure is similar to the structure of voltage gated potassium channels (Kv) built up as homotetramers from subunits with six transmembrane helices (S1-S6). Six TRPV channel subtypes (TRPV1-6) are known, that can be subdivided into the thermoTRPV (TRPV1-4) and the Ca2+-selective TRPV channels (TRPV5, TRPV6). Contrary to Kv channels, TRPV channels are not primary voltage gated. All six channels have distinct properties and react to several endogenous ligands as well as different gating stimuli such as heat, pH, mechanical stress, or osmotic changes. Their physiological functions are highly diverse and subtype as well as tissue specific. In many tissues they serve as sensors for different pain stimuli (heat, pressure, pH) and contribute to the homeostasis of electrolytes, the maintenance of barrier functions and the development of macrophages. Due to their fundamental role in manifold physiological and pathophysiological processes, TRPV channels are promising targets for drug development. However, drugs targeting specific TRPV channels, that are suitable for drug therapy, are rare. Moreover, selective and potent compounds for further research at TRPV channels are often lacking. In this review different aspects of the structure, the different gating stimuli, the expression pattern, the physiological and pathophysiological roles as well as the modulating mechanisms of synthetic, natural and endogenous ligands are summarized.


Assuntos
Analgésicos/farmacologia , Antineoplásicos/farmacologia , Fatores Imunológicos/farmacologia , Moduladores de Transporte de Membrana/farmacologia , Canais de Cátion TRPV/metabolismo , Analgésicos/química , Analgésicos/classificação , Antineoplásicos/química , Antineoplásicos/classificação , Sítios de Ligação , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Humanos , Fatores Imunológicos/química , Fatores Imunológicos/classificação , Ativação do Canal Iônico/efeitos dos fármacos , Ligantes , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Moduladores de Transporte de Membrana/química , Moduladores de Transporte de Membrana/classificação , Modelos Moleculares , Especificidade de Órgãos , Ligação Proteica , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/classificação , Isoformas de Proteínas/metabolismo , Estrutura Secundária de Proteína , Baço/citologia , Baço/efeitos dos fármacos , Baço/metabolismo , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/antagonistas & inibidores , Canais de Cátion TRPV/classificação
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